@article{ref1,
title="Relation between the level of serum vitamin A and visual function",
journal="Zhonghua Yi Xue Za Zhi (Beijing)",
year="1985",
author="Feng, A. L.",
volume="65",
number="12",
pages="743-746",
abstract="<p>[Abstract unavailable]</p><p>Language: zh</p>",
language="zh",
issn="0376-2491",
doi="",
url="http://dx.doi.org/"
}